We all knew thanks to the previews that a "blast from the past" would arrive during the finale party, and we pretty much knew it would be Lydia… Arg and Gemma, however, didn't.
Playing it super cool, suave Arg turned his back, tried to hide, slipped his sunglasses on and then ran away. Even worse, he was dressed as the Fresh Prince of Bel Air as the finale party had a prince and princess theme. Smooth.
Lydia had predicted that sort of response, telling Jessica Wright and Ricky Rayment that he hadn't seen her for about a year and a half. But she added: "I think walking out is a bit immature, really."
Arg did, return, however, and approached Lydia to welcome her back. Clearly, he was overwhelmed – and does he still have feelings for his ex? "If I knew you was here I would have gelled my hair and put on my favourite suit," he admitted.
Lydia said she'd been nervous to arrive at the party but was feeling okay now. Arg told her he'd missed her and the finale ended with him giving her a kiss on the cheek and a cuddle.
Poor Gemma, however, was in tears, as Lydia's arrival came after viewers saw Gemma recently tell Arg she loved him – only to have him not reciprocate.
She told her friends that Lydia would always have that effect on Arg, even though Jess tried to convince her that Lydia had moved on and there'd be no chance of her and Arg getting back together.
Gemma replied: "If it does, it does. It's a shock. Just don't tell James I cried."
Poor Gemma. But thankfully it seems she was in a better mood after the episode aired, tweeting to her followers: "One day my prince will come don't be sad tweeps for me il invite you all to the wedding."
Lydia, meanwhile, tweeted that it was good to be back on TOWIE, suggesting she'll be a regular castmember again once the twelfth season rolls around later this year. Lydia quit TOWIE during the 2012 Christmas special in order to focus on her relationship with then-boyfriend Tom Kilbey, who'd also left the show.
She told Reveal at the time: "It's been really hard for Tom to watch me on TOWIE. So that's why, in order to move forward, I had to make the decision to leave because it was putting a strain on us and making things awkward."
Got an iPad or iPhone? Reveal Mag is specially designed to fit!